Congestive Heart Failure in Cats

Reviewed by Dr. Fiona Lee

Congestive heart failure (CHF) isn't exactly the boogeyman lurking around every corner for cats, but it's serious when it does show up. While heart disease, particularly hypertrophic cardiomyopathy (HCM), is surprisingly common—it affects up to 15% of cats—most cases remain mild or even go unnoticed.¹ Only a smaller percentage of cats with heart disease actually progress to severe issues like CHF or arterial thromboembolism.

Early diagnosis and treatment are critical to helping cats that do develop CHF live longer, happier lives. Learn how to spot the early signs, understand the symptoms and explore the latest diagnosis and treatment options to give your feline friend the best possible chance.

What Is Congestive Heart Failure in Cats?

Congestive heart failure happens when a cat's heart can no longer pump blood effectively, causing fluid to back up into the lungs, abdomen or other parts of the body.² As the heart struggles, oxygen delivery drops and fluid builds up in the tissues, triggering a wide range of symptoms that can become life-threatening.

Unlike other heart conditions, CHF usually strikes after the heart has already suffered significant damage, whether from underlying disease or other contributing factors. This makes early detection critical. The course of CHF can vary: With prompt diagnosis and proper care, some cats can live comfortably for months or even years. Others, unfortunately, may experience a much faster decline in health. The key is catching it early and acting fast.

Types of Heart Disease That Can Lead to CHF

Congestive heart failure in cats typically develops as a complication of underlying heart disease—most often conditions that affect the heart's muscle function or structure. These conditions can gradually weaken the heart, ultimately leading to CHF. Common types of heart disease that may lead to CHF include:

• Hypertrophic cardiomyopathy (HCM): This is the most common form of heart disease in cats. It involves abnormal thickening of the heart muscle, which can reduce the heart's ability to fill properly and pump blood efficiently. HCM is often genetic and can occur in any breed, but certain breeds, like Maine Coons and Persians, have a higher genetic predisposition.¹
• Restrictive cardiomyopathy (RCM): RCM causes the walls of the heart to become stiff, making it harder for the heart to fill with blood. The condition can eventually lead to CHF as the heart becomes less efficient at pumping.³
• Dilated cardiomyopathy (DCM): While rarer in cats, DCM involves the thinning and weakening of the heart muscle, causing the heart chambers to enlarge. This condition impairs the heart's ability to contract and pump blood, which can lead to CHF.⁴
• Arrhythmogenic right ventricular cardiomyopathy (ARVC): This condition leads to abnormal heart rhythms (arrhythmias), particularly affecting the right ventricle. While not as common in cats, it can still lead to CHF if left untreated.⁵

Common Causes of Congestive Heart Failure

While the exact cause of most adult-onset heart disease remains uncertain, factors such as genetics, weight, physical activity and diet are thought to play significant roles.⁶ Recognizing some of the potential causes of CHF in cats can help owners identify risk factors and take proactive steps to manage their cats' health. Below are some common causes of CHF:

 

Primary heart disease

This refers to genetic or acquired heart conditions, such as HCM and DCM, which can lead to heart failure over time.

 

Valve disease

Cats can experience faulty heart valves that impede blood flow, contributing to CHF. This issue can be congenital or a result of age-related changes in the heart.⁷

 

High blood pressure (Hypertension)

Elevated blood pressure can strain the heart and blood vessels, leading to CHF if not managed effectively.⁸

 

Thyroid disease

An overactive thyroid, hyperthyroidism, can contribute to heart disease by increasing heart rate and blood pressure, leading to CHF in the long term.⁹

 

Heartworm disease

While rare, heartworms can affect cats and cause severe heart complications, including CHF. This is more common in regions where heartworm disease is prevalent.⁹

 

 

Signs and Symptoms of Congestive Heart Failure in Cats

 

The signs of CHF in cats can be subtle, especially in the early stages. Cat health issues can be hard to spot as cats often hide their discomfort, making it difficult for owners to notice until the condition becomes more severe. Common signs and symptoms may include:¹⁰

Early warning signs

• Increased lethargy
• Mild coughing
• Rapid or shallow breathing
• Reduced appetite
• Hiding

Moderate to severe symptoms

• Severe fatigue
• Severe coughing
• Respiratory distress
• Loss of appetite
• Weight loss
• Fluid retention

How Is Congestive Heart Failure Diagnosed?

If you suspect your cat may have CHF, a thorough veterinary exam is necessary. The diagnosis of CHF begins with a review of your cat's medical history and a physical exam. Several diagnostic tests may be performed, including:²

• Blood tests
• X-rays
• Echocardiogram
• Electrocardiogram (EKG)

Treatment Options for CHF in Cats

The treatment of CHF in cats depends on the severity of the condition and the underlying causes. Common treatments include:¹¹

• Medications: Diuretics, ACE inhibitors and positive inotropes like pimobendan can help reduce fluid buildup and improve heart function. Beta-blockers may be used for arrhythmias and hypertension, which sometimes go hand in hand with CHF.
• Dietary management: A heart-healthy diet that's low in sodium and high in essential nutrients can help support the heart function. It can also help with other conditions, like diabetes in cats.
• Oxygen therapy: For severe cases, oxygen therapy may be administered to improve oxygen levels in the blood.
• Lifestyle adjustments: Reducing physical activity and stress can help manage the condition. Providing a calm, comfortable environment is key to reducing the heart's workload.
• Surgical options: In some cases, surgery may be required to address underlying causes of CHF, such as heartworm disease or valve issues.⁹

Prognosis and Life Expectancy

The prognosis for a cat with CHF varies depending on the severity of the condition, how well the cat responds to treatment and whether any other health conditions are present. Cats diagnosed in the early stages may live for several years with proper management.¹⁰ However, in advanced stages, CHF can lead to a reduced life expectancy.⁷

Preventing Heart Disease and CHF in Cats

Regular veterinary checkups, especially for older cats or breeds at risk of heart disease, can help detect heart problems early. Managing underlying conditions like hyperthyroidism and hypertension can prevent CHF from developing. Additionally, maintaining a healthy diet and ensuring proper heartworm prevention are crucial steps in keeping your cat's heart healthy.

Pets Best Is Here To Help

If you spot any signs of congestive heart failure in your cat, seek veterinary care immediately. Early treatment can make all the difference. With the right care, many cats go on to live full, happy lives.

Pets Best cat insurance may help you cover the costs of diagnostics and treatment, so you can focus on your cat's health instead of the bills. Plus, policyholders can call our 24/7 Pet Helpline for expert veterinary advice, day or night.

Sources/ Citations

1. "The Feline Cardiomyopathies: 2. Hypertrophic cardiomyopathy," Mark D. Kittleson and Etienne Côté (10/25/2021) Journal of Feline Medicine and Surgery, https://journals.sagepub.com/doi/10.1177/1098612X211020162
2. “Congestive Heart Failure in Cats: Signs, Symptoms & Prognosis," (10/30/2023), Barton Heights Veterinary Hospital, https://www.bartonheights.com/site/blog/2023/10/30/congestive-heart-failure-cats
3. “Heart Disease - Cats," (n.d.), Cummings School of Veterinary Medicine at Tufts University, https://vet.tufts.edu/foster-hospital-small-animals/specialty-services/cardiology/heartsmart/heart-disease-cats
4. “Dilated Cardiomyopathy in Dogs and Cats," Mark D. Kittleson (9/2024), Merck Veterinary Manual, https://www.merckvetmanual.com/circulatory-system/cardiomyopathy-in-dogs-and-cats/dilated-cardiomyopathy-in-dogs-and-cats
5. “Arrhythmogenic Right Ventricular Cardiomyopathy in Dogs and Cats," Mark D. Kittleson (9/2024), Merck Veterinary Manual, https://www.merckvetmanual.com/circulatory-system/cardiomyopathy-in-dogs-and-cats/arrhythmogenic-right-ventricular-cardiomyopathy-in-dogs-and-cats
6. “Heart Disease in Cats," Tammy Hunter et al. (2023), VCA Animal Hospitals, https://vcahospitals.com/know-your-pet/heart-disease-cardiomyopathy-in-cats
7. “Congenital Heart Disorders," (2021), Cornell Feline Health Center, https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/congenital-heart-disorders
8. “High Blood Pressure (Hypertension) in Cats," Elizabeth McCalley (10/20/2021), PetMD, https://www.petmd.com/cat/conditions/cardiovascular/c_ct_systemic_hypertension
9. “Heartworm in Cats," (n.d.), American Heartworm Society, https://www.heartwormsociety.org/heartworms-in-cats
10. “Congestive Heart Failure in Cats: Signs, Symptoms and Prognosis," (7/15/2022), Veterinary Medical and Surgical Group, https://www.vmsg.com/site/blog/2022/07/15/congestive-heart-failure-cats
11. “Congestive Heart Failure (CHF) in Cats," (n.d.), Animal Care Center of Green Valley, https://animalcarecenter.com/services/congestive-heart-failure-chf-in-cats/